Refrigerating apparatus



y 1931. .1. G. KING REFRIGERATING APPARATUS Filed July 22, 1926 Jwuenfow May 19; .1931

UNITE STA TBS.

man G. KING, OF DAY'IOK, OHIO ASSIO-NOB, BY MES'NE ASSIGNMENTS, TO rnremm CORPORATION, A. CORPORATION OF DELAWARE 'mmenaarme Armim'rns Application filed July 22,

The present invention relates to controllers for refrigerating s stems, and particularly to controllers for a ecting the degree of refri eration.

practice of mechanical refrigeration, it is necessa that some apparatus be operated at a relatlvely lower average temperature than other apparatus. For example, it is desirable to maintain the avera e temperature of the cabinet of a househol refrigerating apparatus at approximately 45 F., while in other refrigerating apparatus, such as used with ice-cream cabinets, it is necessary to maintain an average temperature considerably below freezing point. In either system it is desirable to provide a relatively fine adj ustment of a controller, whereby to start and stop the refrigerating cycle at any desired temperatures within certain limits. To facilitate the economical manufacture of refrigeratin systems, it is desirable to utilize one contro er which is adaptable to different apparatus. One of the objects of the present invention is to provide a controller which can be adapted for use with different refrigcrating apparatus which operate to produce refrigeration at different average temperatures, said controller being provided with meansfor securing a relatively fine adjustap aratus.

urther objects and advantages of the pres ent invention will be a parent from the following description, re erence bein had to the accompanying drawings, wherem a preferred form of the present invention is clearly shown.

Inthedrawings: Fig. 1 is a partly-sectional and partly-elevational view of a controller; s Fig. 2 is a fragmentary sectional view of a portion of said controller, showing certain elements in one position; and

Fi 3 is a view similar to Fig. 2, but showements in a different position.

platform 29, to one end 0 which there is secured a metal bellows 21 which is connected with a tube 22. Tube 22 is refer-ably con- I l meted on the low-pressure si e-of therefrigment when the controller is utilized with anyin e the springs 39 and also aids in preserving ileferring to the drawin there is shown a 1926. Serial 1T0. 124,160.'

crating system and, therefore, adapted to contain a refrigerant, and is likewise responsive to the pressure within said low-pressure side. A frame 24 is carried by the platform 20 and is provided with'ears, one of which is shown at 25. An 0 erating member 26 is-pivotally mounted at 2 upon the ears 25. Lever 26 is pivotally connected at 28 with ears, one of which is shown at 29, carried by the top wall 30 of bellows 21. It is apparent that lever 26 will be rotated about pivot 27, in response to the pressure within the bellows 21.

A yoke 32 is carried on the other end of platform 20 and the head 33 of lever 26 extends between the legs of said yoke. A bushing 34 is secured to the top wall of yoke 32 by a nut35. A plunger 37 extends through the bushing 34, and is disposed in the path of movement of head 33 of. lever 26. Plunger 37 is provided with anenlarged portion 38' adapted to limit the downward movement of said plunger and adapted to provide a shoul der for coil springs 39. and 40, which are disposed within the bushing 34. The exterior portion 'of the bushing 34 is screw-threaded and is adapted to be received by an adjusting nut 42 adapted to be locked in position by a locknut 43. A washer 44 is located within the nut 42, and springs 39 and 40 are adapted to be interposed between said washer 44 and 80 the shoulder 38. Washer 44 prevents twistin of the springs while the device is being adJuSted but it is not essential. In Fig. 2, spring 39 only is shown effective; and in Fig. 3 the nut 42 has been moved to a position in which both s rings 39 and 40 are effective. Springs 39 an 40 are woundoppositeiy to one another, so as to prevent the coils of spring 40 from moving into the spaces between the coils of sprin 39.

An examination of t e drawings will disclose the simplicity of'the controller. The members 34 and 42 provide both a casing and an adjusting means. The reverse position of as the adjustment disclosed in Fig. 3. 'As the member 42 is screwed down, the force'of compression travels clockwise, looking down, through the clockwise wound coils'of the spring 39. Accordingly the reaction of the spring 39 against this compression is in an anti-clockwise direction against the compressing member. As the ad acent spring 40 is oppositely wound in a counter clockwise dlrectlon, its reaction is 1n a clockwise d1rec tion to the force of compression; 'Accordingly these two reactions being opposite to one another will tend to neutralize each other and will not tend to disturb the adjustment.

If both springs were wound the same way,

the reaction of both of them against the member 44 or the member 42 if the member 44 were not used might tend to exert a couple that would tend to loosen the adjustment in case the apparatus is jarred or vibrated frequently. Thus the oppositely wound adjacent springs tend to maintain the adjustment.

The underside of platform 20 carries a contact block 45, upon" which there is mounted a stationar contact 46 and a movable contact 47 pivotall y mounted at 48, which contacts are connected, respectively, with conductors 49 and 50. A lever 52 is pivotally mounted at 53 upon the lever 26 and a link 54 is pivotall connected with lever 52 by a pin 55. Linl 54 is also pivotally connected with movable contact 47. The opposite end of lever 52 is provided with camming surfaces 56 and 57, which are arranged to cooperate with a roller 59 carried by a roller bracket 60 which is pivotally mounted at 61 upon the legs of yoke 32. A spring 62 is wound around the pivot 61 and the ends thereof engage a pin 63 and the bracket 60, whereby said spring normally' tends to move the roller bracket 60 and, likewise, the roller 59 to the right, as viewed in I wardly. A stop 64, carried by the pivotally- Fig. 1. When the spring-pressed roller 59- cooperates with the camming surface 56, it normally tends to'maintain the lever 52 in the position shown in Fig. 1. However, when said, roller en ages camming surface 57 it maintains the ever 52 in such position that contact 47 engages contact 46.

When the 'ressure within the bellows increases, the ever 26 is moved upwardly,

thereby causing the lever '52 to-be moved up mounted contact 47, engages the top wall of block 45 and limits the counterclockwise movement of contact 47 and, likewise, limits the upward movement of the'right-ha'nd end of lever 52; Therefore, on the upward movement of lever 26,1ever52 will fulcrum about pin and the camming surface 56 will'be the roller will coo moved over the roller 59, and when the lever 52 has moved beyond the dead center position, formed by the camming surfaces 56' and 57,

perate with camming surfaces 57 to uickly rotate thelever 52 about pivot 53 an cause contact 47 to;engage contact 46. Since the plunger 37 lies within the path of movement'of head 33 of-leyer 26, the

. aforementioned upward movement of lever 52 is resisted by the spring 39, or, if both springs are operative, by springs39 and 40.

-weaver.

lever 26 is moving upwardly. The construe tion of the mechanism is such that the head 33 will move away from the plunger 37 before the lever 52 is moved beyond the dead center position, the enlarged portion on shoulder 38 limiting the downward movement of plunger 37. Therefore,the springs are rendered ineffective and the ressure, at which thecontacts are separated is controlled by either of the adjustable tension springs 65- or 66. f

When the controller is utilized in a refrigerating system for cooling ice-cream cabinets or the like in which a relatively low temperature is desired, the nut 42 is substantially in the position shown in Fig. 2, in which posi-' tion spring 40 is not utilized; and the nut 42 being adjustable with respect to the bushing 34, permits the regulation of the tension of sprin 39, whereby to control the resistance of sai spring. Thus it is apparent that since spring 39 is longer than spring 40, a relatively wide range of adjustment may be had without bringing the spring 40 into operation. However, if it is desirable to utilize the present controller for. an apparatus for cooling the household refrigerator cabinet, or the like, in which a relatively higher temperature is desirable, the nut 42 is movedto substantially the osition shown in Fig. 3,;in which position t e spring 40 augments the resistance offered by the spring 39. The springs 39 and 40 may be more or less compressed by the nut 42 to thus vary the resistance offered to the upward movement of lever 26.

It is apparent from the foregoing that a controller has been provided which may be accurately adjusted to respond to slight pressures'within a certain pressure range andwhich may be accurately adjusted to respond to relatively different pressure ranges.

It is also apparent that by virtue of the:

disclosed spring arrangement, there has been provided a controller in which certain elements thereof may be made compact-while at the same time maintaining sufiicient flexiadjustment, for the purbility for accurate pose heretofore specified. The springs 39 and 40 provide a resistance device having variableresistance characteristics, When onl one spring is utilized, the resistance offered t ereby has a difierent resistant characteristic than when both are utilized. By providing a resistanee device having variable resistance characteristics, a relatively fine adjustment may be had when operating within a certain range of pressure and when operating within a relatively different range. By providing two superimposed springs of diii'erent lengths, short springs can be used thus ob taining compactness while still maintaining relatively fine adjustments as described.

The present invention has been described as applied to the low-pressure side of a refrigerating system. It is to be understood, however, that the control may be responsive to different sources of pressures. 7

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A controller for a refrigerating system comprising in combination an operating -member responsive to conditions in the system, and a resistance member for said operating member comprising an adjustable caslng, a plurality of spring members inside the casing adapted to resist the movement of said operating member in one direction, the adjustment of said casing determining the number of spring members made operative.

2. A controller for a refrigerating system comprising in combination an operating member responsive to conditions in the system, and a resistance member for said operatingmember comprising an adjustable casing, a shaft passing axially through said casing and positioned to bear against said operating member, an enlarged portion on said shaft within said casing, a plurality of spring members within said casing adapted to exert pressure against said enlarged porber, an enlarged portion on said shaft within said casing, spring members bearing against said enlarged portion, the adjustment of said screw-threaded members u on each other determining the number 0 made operative to oppose movement of said shaft.

In testimony whereof I hereto aflix my signature.

JESSE G. KING.

tion and thus resist movement of the shaft adapted to be screwed over said outside screwthreaded member to form the casing, spring members inside said casing adapted to resist movement of said operating member in one direction, the adjustment of said inside screw-threaded member determining the number of spring, members made operative to resist movement of said operating member.

4. A controller for a refrigerating system. comprising in combination an operating member responsive to .conditions in'the system, and a resistance member for said operating member comprising an adjustable casing comprising an outside screw-threaded memspring members 

